1. Field of the Invention
The present invention relates to a vehicle front structure, an activation controller for occupant protection apparatus, and a method of production of the vehicle front structure.
2. Related Background Art
In these years, there is a known vehicle front structure in which a bumper reinforcement (hereinafter referred to as a bumper R/F) is supported at the front ends of side members located on right and left sides of a vehicle and in which, in the event that the vehicle collides with an obstacle at the bumper R/F first, the side members will undergo compressive deformation to absorb the impact.
For example, Japanese Patent Application Laid-Open No. 2002-2528 discloses a body structure for absorbing the impact by deformation of the side members. In this body structure, a chassis cross member extending laterally is provided below the right and left front side members. Connections between arms extending upward from the chassis cross member, and the front side members are arranged as separable in the event of collision, so as to properly deform the front side members.
On the other hand, more and more vehicles are being equipped with occupant protection apparatus such as airbags in recent years. When such a vehicle runs into an obstacle at high speed, i.e., when the deceleration of the vehicle exceeds a certain preset level, the occupant protection apparatus is activated to protect occupants.
FIG. 8A and FIG. 8B show an example of graphs showing temporal changes of deceleration (negative acceleration) of a vehicle. FIG. 8A shows the vehicle deceleration upon a collision at low speed, and FIG. 8B the vehicle deceleration upon a collision at high speed. An activation determination method for the occupant protection apparatus is, for example, a method of setting a determination area A in the graphs shown in FIGS. 8A and 8B and activating the occupant protection apparatus when the deceleration reaches the determination area A.